Floor covering with skid-proof undercoating

ABSTRACT

A floor covering with a skid-proof underside consisting of a mixture of atactic polypropylene and filler.

Emilie tates Patent [72] Inventors Gunter Stichter Frankensteiner Strasse 119, 61 Darmstadt- Eberstadt; Josef Sulo, Obermainstrasse 21, 6 Frankfurt am Main; Manfred Schweizer, Friedrich-Ebert-Strasse 32, 6101 Gross- Bieberau, all of Germany [21] Appl. No. 683,453 [22] Filed Nov. 16, 1967 [45] Patented Dec. 14, 1971 [32] Priority Nov. 17, 1966 [33] Germany [31 C 40718 [54] FLOOR COVERING WITH SKID-PROOF UNDERCOATING 8 Claims, No Drawings [52] U.S. C1 117/76 A, 117/161 UF, 117/161 UB 117/161 UZ, 161/67,

[51] Int. Cl ..B32b 27/20. B32b 27/32 [50] Field of Search 1 17/76 A, 161 UH, 138.8 A; 161/67,66

[56] References Cited UNlTED STATES PATENTS 3,142,611 7/1964 Mills l6l/67 X 3,166,465 l/l965 Rahmes 161/66 2,927,047 3/1960 Schulde etal.. 117/161 X 3,079,278 2/1963 Naudain 117/161 X FOREIGN PATENTS 972,668 10/1964 Great Britain 161/67 1,089,563 11/1967 Great Britain 161/67 Primary Examinerwilliam D. Martin Assistant Examiner-D. Cohen Almrneys-Gordon W. Hueschen and Hueschen and Kurlandsky ABSTRACT: A floor covering with a skid-proof underside consisting ofa mixture of atactic polypropylene and filler.

FLOOR COVERING WITH SKID-PROOF UNDERCOATING This invention relates to floor coverings with skidproof undercoatings and to a process for making such floor coverings.

It has been known that floor coverings made of rugs, PVC, linoleum and cork can be covered on their undersides with coatings. This coating of floor coverings on their undersides brings about both an increase of their useful life and an essential improvement of their insulation against cold, heat, in their sound absorption and imperviousness to the sound of footsteps. There are innumerable processes which deal with the finishing of the underside of floor coverings.

in order to preserve the characteristics of the upper layer of a floor covering as long as possible, as well as in order to increase and improve the insulating characteristics of the entire floor covering, the underside is provided with insulating and absorbing substances which can be either of an organic or inorganic origin. For the improvement of sound absorbing characteristics and the characteristics for absorbing the sound of footsteps and for insulating floor coverings against heat and cold, quite generally a jute felt, a jute felt web, a jute felt fabric, a wool felt, wool felt fleece, wool felt fabric, felted woolen board, preimpregnated felted woolen board, fully impregnated felted woolen board, coconut fiber fabric, excelsior, glass wool, asbestos fiber, rockwool, bituminous cork felt, webs of cork, cork felt, cork cement (Korkzement," TM), etc., were used either in their natural state or with various substances which were provided with strength improving and/or water repellent substances.

Joining together these various materials, namely the top layer of the floor covering with the lower layer of the floor covering, can be accomplished, for one thing, in a mechanical manner, such as for example by stitching it together and, for another thing, with the help of chemical auxiliary substances, especially with the help of adhesive substances, which can be used on a sizing basis, starch basis, basis of urea-formaldehyde synthetic resin or on the basis of various plastic dispersions, such as polyvinyl acetate, polyvinyl propionate, polyacrylic ester and others, which can be used either as homopolymerizates with or without outside softening or heteropolymerizates with inside and/or outside softening.

Processes in which the undercoating of rug-type floor lining materials are made with the help of rubber latex are used quite frequently. A natural rubber latex and/or synthetic rubber latexes or their mixtures can be used. Particularly for production of knop rugs and tufted rugs, one will use a finishing on the basis of rubber latex on the underside.

Quite apart from what kind of finishing was to to the underside of the floor covering, according processes used hitherto it is customary to lay the floor coverings by way of cementing them, in order to avoid any danger of slipping, any uneveness, any waviness and any rolling up in the floor covering. in order to save the process of cementing during laying of the floor covering, which is troublesome, uneconomical and has many disadvantages, many efforts have been made to finish the underside of the floor covering in such a manner that an immediate, rational and quick laying or cementing of the floor coverings can be made also by not fully qualified personnel.

Numerous proposals deal with the solution of this question. On the one hand, we are dealing, for example, with pads for rugs which are supposed to do away with any danger from slipping, such as jute-type fabrics saturated with rubber latex, various lattice types of fabrics, which have been prepared with slightly gluey plastics, in order to achieve an adhesive substance on both sides or else webs on the basis of a polyvinyl chloride foam or webs of polyurethane foam. On the other hand, we are dealing both with paddings with a waffle-type rubber coating on the underside and with floor coverings whose undersides consist of a strengthened and/or structured fleece or felt, and whose surface had also been finished with rubber latex or with synthetic material giving adhesion.

It has also been known to provide the underside of floor coverings with automatic adhesives. The advantage of such a process as compared to the traditional cementing of floor coverings with the help of liquid cements consists in the fact that the floor covering can be laid without any obnoxious odor coming from the adhesive and without additional tools, by anyone and quite expertly, provided that the subfloor has no uneven parts, no cracks due to tension or settling, that it is completely dry, not porous or rough and not soiled by oil, wax, lacquer or splashes of paint.

This process has the additional advantage in that in the event of any mistakes made in the laying, the covering can be pulled off again relatively without trouble, can be finished anew and laid over again, something which is not possible in the case of the above-mentioned liquid floor cements because of absorption of the adhesive. But the disadvantage also 0pposes this, namely that the underside of the floor covering provided with the automatic adhesive must under all circumstances be provided with a separating agent, customarily siliconized paper, since otherwise this self-adhesive will stick to the upper side of the floor covering during stacking, unrolling, transportation or storage, so that not only will the surface be soiled but also the adhesive force will be lost, quite apart from the fact that the covering, upon contact with the self-adhesive undersides against one another, will be stuck together so fast that a separation will not be possible without damage to the coating. As a result of that, an added difficulty arises, since pulling off the above-mentioned protective layer must be accomplished manually and thus, through contact with the selfadhesive underside of the covering, this will result in a considerable dirtying of one's hands, so that soiling the floor coverings can only in practice be avoided with considerable difficulty. But this should be prevented under all circumstances, particularly in the case of rug covered floors, since spots often can no longer be eliminated without trace.

A further disadvantage will be that in practice this adhesive does not have any heat or cold insulating properties or sound absorbing or footstep sound absorbing quality, so that only the laying through self-adhesion as such will represent an improvement, whereas, however, the application of the layer on the underside of the covering would still have to be accomplished separately just as before, for the purpose of increasing the life expectancy in use and the cold and heat insulating and sound and footstep sound absorbing properties.

Surprisingly, it has been found that skidproof coverings with an excellent behavior are obtained by coating the underside of the floor covering with a mixture of a thermoplastic material and a filler. Optional components of such a coating mixture are plasticizers and pigments. The new coating according to the invention, which is plastic within the temperature range of its use which is intended for the underside of floor coverings, will increase the life span of the floor covering, is waterproof, water repellent, nonrotting, moth and insect proof.

On the basis of the fact that the coating is a plastic mass, the edges of the coating after the floor covering has been laid join completely against one another, and they pass over into one another completely and without any seams through later pressure by footsteps. It will also be possible to smooth out invisible, smaller seams which might have developed as a result of slanting walls, baseboards and similar things, through a slight stretching at the locking point.

Previously, it was necessary according to DIN 18,365, to prepare the subfloor prior to laying the covering for suitability to cover it with the prescribed basic coating for the rug, which was therefore expensive and time consuming. The presupposition for the conditioning of the subfloor required for laying a rug floor covering was in this case: no major uneveness of the subfloor; no cracks from tensions and settling in the subfloor; sufficiently dry and firm subfloor; no porous or rough subfloor; fairly large surfaces had to be troweled off first, to be smoothed out and sanded; impurities of the subfloor, for example from dirt, oil, wax, varnish or spots of paint, were to be eliminated carefully; an incorrect position as to height of the surface of the subfloor in relation to the vertical position of adjoining parts of the structure had to be adjusted and other similar work had to be carried out.

With the new type of floor covering whose underside is provided with a plastic coating mass which is new and which according to the invention resists sliding, it will be possible to lay these floorings even without previous preparations, that is to say, completely independently of the fact as to whether the subfloor is uneven, shows blisters, cracks, is damp, porous, is soiled with oil, wax, varnish or paint spots, is rough, dusty or granular, for even extremely uneven subfloors will be leveled.

The new floor covering equipped with the coating mass according to the invention can be laid without preparation of the subfloor directly on concrete, stone or tile floors, anhydride mortar floors, cement floors, magnesia mortar floors, plaster floors, xylolith mortar floors and floors made of synthetic materials, furthermore on plank floorings and poured asphalt, cork brick, foam plate (foam tile) and on PVC, linoleum, bituminous felt floors, etc.

These novel floor coverings can be used either in webs, in plates or tiles. At the same time, it will be of particular advantage that during the laying of the floor covering there will be practically no waste through trimming in the same hue, since as a result of the new plastic underside of the covering even the smallest remnants can be used, which can be fitted in without seams.

A further advantage in the case of the use of this new type of floor covering, whose underside has been provided with the new plastic mass for coating according to the invention and which is skidproof, in the shape of tiles or plates, consists in this, that it can be stacked without the need for a separating agent and that it can be separated again without difficulty. These plates or tiles are stacked in two's, one against the other, each time with the bottom side of the coverings meeting the bottom side of the other; they are transported that way or stored in that manner. The advantage as against all other customary floor coverings provided with self-adhesives thus becomes obvious.

The new type properties according to the invention of the floor covering will be achieved through the fact that a plastic covering mass comprising a thermoplastic material and a filler and, as the case may be, plasticizers, pigment and other additives are applied to the underside of a web. The ratio of the individual components is selected in such a manner that the end result will be a plastic mass without rubber elasticity or other recoil properties. The covering mass must not only be plastic and amorphous during finishing and application to the rear of the course of the floor covering, but it must also possess plastic and amorphous characteristics in the temperature range in which it is used, that is to say at room temperature. The preferred thermoplastic materials are polyolefines, such as polyethylene, polypropylene, polyisobutylene, and polybutylene. Of particular importance for this invention is the use of atactic polypropylene as thermoplastic material. Other suitable thermoplastic materials are polyacetal, polystyrene, polyacrylonitrile, polyacrylic ester, polymethacrylic ester, polyvinyl chloride, polyvinylidene chloride, polyvinyl acetate, polyvinyl acetal, polyvinyl ether, polytetrafluoroethylene, polyamide, cumarone indene resins, natural resins and others. The preferred thermoplastic materials employed in accordance with this invention have a softening range between 90 and 220 (1., preferably between l20 and 220 C.

The following can be used as fillers, for example: finely ground quartz, asbestos, talcum powder, chalk, kaolin, slate flour, wood dust, cellulose flour, light spar, pearl white barium sulfate, graphite and so forth. Inorganic fillers are preferred.

The following can be used as plasticizers: esters of polybasic acids with monovalent alcohols, such as for example: phthalic acid ester, ester of adipic acid, ester of sebacic acid, polyglycol fatty acid ester, thiodibutyric acid ester, polyglycol fatty acid diester, tricresyl phosphate, other phosphates, paraffin sulfonic acid phenyl/cresyl ester, parafiin oils, aromatic oils, chlorinated aromatic substances, chlorinated paraffin oils, etc. Paraffinic substances such as paraffin oils and high molecular weight paraffins are particularly suitable as plasticizers. One can use organic as well as inorganic pigments.

While it is possible to vary the amount of the components of the coating composition within broad ranges, it is advisable to use 20 to 90, preferably 40 to 80, parts of the thermoplastic material for 5 to 60, preferably 25 to 50, parts of filler. The amount of the optional components with regard to the already specified amounts of the main components can vary between 2 to 25 parts of the plasticizer and 0.5 to 5 parts of pigment.

The thermoplastics are melted down, are treated with plasticizers and mixed homogeneously with fillers, pigments and, if required, further additives. This is accomplished in a generally known manner in stirrers, mixers, kneaders, etc. The application of this coating mass to the underside of the web, for example through extruding, painting, calendering and so forth, offers no difficulties and can be accomplished in any desired manner.

The application of the coating mass to the underside of the floor coverings therefore takes place in a molten state at an increased temperature. When using this process in the case of rug covering material, if we are dealing with a polyamide and/0r polypropylene tufted felt or tufted web, we will have a textile floor covering in which the chemical fibers are attached firmly anchored and welded together in the plastic mass, which fact produces a hitherto unknown strength in the floor covering. The coating mass is to be applied to the web on the underside in such a manner that a closed (tight) surface will develop, which will close the entire backside. The thickness of the application may amount to 0.1 to 30mm, especially 0.5 to 15 mm. The floor coverings coated in accordance with this invention have an upper or top layer formed by a textile or fibrous material.

The skidproof property, which is very good anyway, may be still increased by embossing the surface of this coating in such a manner that when laying the material, a vacuum will develop between the subfloor of the floor and the plastic profile mass of the floor covering, as a result of which its adhesion and skidproof properties will be further increased. In accordance with a particular embodiment of the invention, it is advantageous to apply to the underside of the floor covering coated with a mixture of a thermoplastic material and a filler and, as the case may be, a plasticizer and a pigment, a contact adhesive preferably in the form of a dispersion, such as an aqueous dispersion.

The parts are by weight.

EXAMPLE l Fifty parts by weight of a polyethylene, whose molecular weight amounts to 50 to 60,000 and which has a softening point according to "Ring and Ball (name of a test, TM) of C., is molten at C. and is plasticized with 5 parts by weight of a parafiinic oil with a molecular weight of 400 to 600, to which 5 parts by weight of ultramarine are added. To this are added in portions 100 parts by weight of chalk and are mixed in homogeneously. This mass is applied with the help of an extruder to a polyamide tufted web, weighting 500 gJmF, at a temperature of 150 C., in such a manner that the final weight of the rug floor covering will amount to 4,000 gJmI". After the mass is cooled off, a profiling is put onto this coating mass with the help of embossing rollers and the covering is punched into tiles or plates of 30x30 or 50x50 cm., which are stacked in pairs, each time with the underside against another underside.

EXAMPLE 2 Forty-five parts of a polypropylene with a softening point of Ring Ball" of M3" C. are melted with 7 parts of a 2,000 with the melting point of C., and this melt is plasticized with 5 parts of an aromatic oil. Subsequently, while stirring continuously 80 parts of ground shale are added and this mass is applied with the help of a calender at a temperature of 135 C. to a polypropylene needle felt. The quantity of the coating amounts to 2,000 gJmF, After the coating has cooled down, just as in example 1, the coating mass is stamped and from this will originate the direction for laying the squares of carpet punched out later on. One will obtain a slip-proof textile floor.

EXAMPLE 3 Forty parts of a polybutylene with a softening point of Ring Ball" of 156 C. are melted at 170 C. together with 12 parts of a paraffin with a melting point of 54 C., and this melt was mixed with 35 parts of asbestos powder in a kneader, and subsequently they are applied by means of a heated doctor blade to a tufted carpet. The applied covering amounts to 3,000 g./m. the total weight of the underside of the carpet 4,500 g./m.

EXAMPLE 4 Fifty parts of a polyisobutylene with a softening point of Ring Ball" of 130 C. are melted in a heated stirrer at 160 C. Fifteen parts of cumarone indene resin with a melting point of 75 C. are inserted and after homogenizing with 25 parts of quartz powder, parts of microtalcum as well as 1 part of iron oxide red, are added. This mixture is applied at 160 C. with the help of a hot dispenser on a Nylon velour fabric. The quantity applied is 1,200 g./m. The carpet coated in this manner is slip-proof.

EXAMPLE 5 EXAMPLE 6 Thirty parts of polyvinyl acetate with a softening point of Ring Ball of 170 C. are melted at 185 C. and are mixed in a planetary stirrer with 10 parts of dioctylphthalate and 10 parts of tricresyl phosphate. Fifty parts of powdered graphite are added to this softened melt in portions. The finished mass is applied with a heated doctor blade at 180 C. to a floor covering. Weight of the covering is 1,500 g./m. The floor covering is slip-proof.

EXAMPLE 7 Forty parts of a blown special bitumen with a softening point ofRing Ball" of 95 C. are mixed in a heated kneader with 8 parts of a normal (standard bitumen with a softening point of Ring Ball of 58 C. and 80 parts of heavy spar (barrite) and 12 parts of asbestos fibers are added to this melt. This mass is applied with the help of an extruder at 140 C. to the underside of a textile floor covering. The quantity of coating is 3,500 g./m. The floor covering is slip-proof.

EXAMPLE 8 Thirty-six parts of an atactic polypropylene with a softening point ring and ball of 155 C. are made to melt in an oil heated container at 200 C. and subsequently are mixed in a horizontal stirrer with 40 parts of heavy spar at a temperature of 160 C. The finished mass, with a temperature of 160 C., is applied to a Nylon-needle felt web via a heated drain channel through a sieve. Said web passes at a speed of 5-12 rn./min. through a heated roller rotating in the opposite direction, which accomplishes an even application and distribution of the coating mass on the carpet web. The coated carpet web passes through a cooling zone, which is 15 m. long, at the end of which the coating is profiled and the web is cut into plates with the help of a crosscutter. These plates are then punched out after 24 hours of storage into floor tiles.

EXAMPLE 9 Forty-two parts of an atactic polypropylene with the characteristics as in example 8 are plasticized with 8 parts of a low molecular (liquid) polyisobutylene. This softened melt IS mixed with 50 parts of chalk. This mass is applied just as in example 8 to a textile floor covering. Before arrival of the thermoplastically coated carpet web into the cooling zone, an approximately 50 percent dispersion on an acryl resin basis with adhesive properties is sprayed by means of several spray guns onto the still warm thermoplastic, in such a manner that the available quantity of energy is utilized for the evaporation of the liquid of the dispersion. In this case an additional cooling effect of the thermoplastic will be achieved at the same time. The applied quantity of the contact adhesive amounts, according to choice, to 100-200 g./m.

The automatically adhering carpet web, after passing the cooling zone, is covered on its coated side with a polyethylene foil of 50 m. thickness and is cut into plates and punched out according to example 8.

Various modifications and equivalents will be apparent to one skilled in the art and may be made in the products, compositions, and method of the present invention without departing from the spirit or scope thereof, and it is therefore to be understood that the invention is to be limited only by the scope of the appended claims.

We claim:

1. A floor covering with a skidproof underside consisting essentially of a mixture of 20 to 90 parts of atactic polypropylene and 5 to 60 parts of a filler, which underside is plastic at normal temperatures.

2. A floor covering as claimed in claim 1 wherein said mixture further contains 2 to 25 parts of a plasticizer.

3. The floor covering of claim 2 wherein the plasticizer is isobutylene.

4. A floor covering as claimed in claim 1 wherein said mixture further contains 0.5 to 5 percent of a pigment.

5. A floor covering of claim 1 with a top layer of a textile material and a skidproof underside, wherein the underside of the floor covering consists essentially of a mixture of 40 to parts of a atactic polypropylene and 25 to 50 parts of an inorganic filler.

6. A floor covering as claimed in claim 5, wherein said mixture further contains 2 to 25 parts of a plasticizer.

7. A floor covering as claimed in claim 5 wherein said mixture further contains 0.5 to 5 percent of a pigment.

8. A floor covering as claimed in claim 5 wherein on the underside of said coated floor covering a contact adhesive has been applied.

UNITED STATES I PATENT OFFICE CERTIFICATE OF CORRECTION \Patent 3,627,566 Dated December 14, 1971 lnventofls) Gunter StiChter, Josef Sulo and Manfred Schweizer It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Col. 1, line 49 "to to" Page 2, line 21 applied to Col. 1, line 50 "according processes" Page 2, line 22 according to processes Col, 1, line 52 "uneveness" Page 2, line 25 unevenness Col. 2, line 66 "uneveness" Page 5, line 24 unevenness Col. 4, line 66 Ring Ball" Page 10, line 16 "Ring Bal1"- Col. 4, line 66, at end of line "2000" Page 10, line 17 polyamide Col, 5, line 49 "(s tandard" Page 12, line 6 (standard) Signed and sealed this 6th day of June 1972.

(SEAL) Attsst:

EDWARD MJLETQHER, JR. ROBERT GOTTSCHALK testingcfflcer Commissioner of Patents ORM PO-IOSO (10-69) USCOMM-OC 60376-P69 w 0.5. GOVERNMENT PRINTING orncz: um c-ass-an 

2. A floor covering as claimed in claim 1 wherein said mixture further contains 2 to 25 parts of a plasticizer.
 3. The floor covering of claim 2 wherein the plasticizer is isobutylene.
 4. A floor covering as claimed in claim 1 wherein said mixture further contains 0.5 to 5 percent of a pigment.
 5. A floor covering of claim 1 with a top layer of a textile material and a skidproof underside, wherein the underside of the floor covering consists essentially of a mixture of 40 to 80 parts of a atactic polypropylene and 25 to 50 parts of an inorganic filler.
 6. A floor covering as claimed in claim 5, wherein said mixture further contains 2 to 25 parts of a plasticizer.
 7. A floor covering as claimed in claim 5, wherein said mixture further contains 0.5 to 5 percent of a pigment.
 8. A floor covering as claimed in claim 5 wherein on the underside of said coated floor covering a contact adhesive has been applied. 